Abstract: An eggshell catalyst useful for a Fischer-Tropsch (FT) synthesis or other reactions comprises a homogeneously dispersed transition metal and a promoter situated in an active phase in a precisely selected outer region of a catalyst pellet. The active phase region is controlled to a specific depth, which permits the control of the catalysts selectivity, for example, the size of the hydrocarbon chains formed in the FT process. A method of preparing these eggshell catalysts involves a non-aqueous synthesis where polar and non-polar solvents of relatively low vapor pressure are employed to define the depth of penetration of metal species in a refractory oxide substrate, which is followed by fixing and activating metallic catalytic species in the structure by calcination of the catalyst particles.